mirror of
git://git.sv.gnu.org/coreutils.git
synced 2026-04-20 18:56:39 +02:00
ba6582e95c
Previous behavior failed to read contents of a (re)appearing file, when symlinked by tail's watched file. Also we now diagnose other edge cases when running in inotify mode, where an initially missing or regular file changes to a symlink. * src/tail.c (main): If any arg is a symlink, use polling mode. (recheck): Diagnose the edge case where a symlink appears during inotify processing. * tests/tail-2/symlink.sh: Test the fix. Mention the edge cases. * tests/local.mk: Reference the new test. * NEWS: Mention the fix. Reported by: Ondrej Oprala
79 lines
3.3 KiB
Bash
Executable File
79 lines
3.3 KiB
Bash
Executable File
#!/bin/sh
|
|
# Ensure tail tracks symlinks properly.
|
|
|
|
# Copyright (C) 2013 Free Software Foundation, Inc.
|
|
|
|
# This program is free software: you can redistribute it and/or modify
|
|
# it under the terms of the GNU General Public License as published by
|
|
# the Free Software Foundation, either version 3 of the License, or
|
|
# (at your option) any later version.
|
|
|
|
# This program is distributed in the hope that it will be useful,
|
|
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
# GNU General Public License for more details.
|
|
|
|
# You should have received a copy of the GNU General Public License
|
|
# along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
|
|
print_ver_ tail
|
|
|
|
# Function to check the expected line count in 'out'.
|
|
# Called via retry_delay_(). Sleep some time - see retry_delay_() - if the
|
|
# line count is still smaller than expected.
|
|
wait4lines_ ()
|
|
{
|
|
local delay=$1
|
|
local elc=$2 # Expected line count.
|
|
[ "$( wc -l < out )" -ge "$elc" ] || { sleep $delay; return 1; }
|
|
}
|
|
|
|
# Ensure changing targets of cli specified symlinks are handled.
|
|
# Prior to v8.22, inotify would fail to recognize changes in the targets.
|
|
# Clear 'out' so that we can check its contents without races.
|
|
:>out || framework_failure_
|
|
ln -nsf target symlink || framework_failure_
|
|
timeout 10 tail -s.1 -F symlink >out 2>&1 & pid=$!
|
|
retry_delay_ wait4lines_ .1 6 1 || fail=1 # Wait for "cannot open..."
|
|
echo "X" > target || fail=1
|
|
retry_delay_ wait4lines_ .1 6 3 || fail=1 # Wait for the expected output.
|
|
kill $pid
|
|
wait $pid
|
|
# Expect 3 lines in the output file.
|
|
[ $( wc -l < out ) = 3 ] || { fail=1; cat out; }
|
|
grep -F 'cannot open' out || { fail=1; cat out; }
|
|
grep -F 'has appeared' out || { fail=1; cat out; }
|
|
grep '^X$' out || { fail=1; cat out; }
|
|
rm -f target out || framework_failure_
|
|
|
|
# Ensure we correctly handle the source symlink itself changing.
|
|
# I.E. that we don't operate solely on the targets.
|
|
# Clear 'out' so that we can check its contents without races.
|
|
:>out || framework_failure_
|
|
echo "X1" > target1 || framework_failure_
|
|
ln -nsf target1 symlink || framework_failure_
|
|
timeout 10 tail -s.1 -F symlink >out 2>&1 & pid=$!
|
|
retry_delay_ wait4lines_ .1 6 1 || fail=1 # Wait for the expected output.
|
|
ln -nsf target2 symlink || framework_failure_
|
|
retry_delay_ wait4lines_ .1 6 2 || fail=1 # Wait for "become inaccess..."
|
|
echo "X2" > target2 || fail=1
|
|
retry_delay_ wait4lines_ .1 6 4 || fail=1 # Wait for the expected output.
|
|
kill $pid
|
|
wait $pid
|
|
# Expect 4 lines in the output file.
|
|
[ $( wc -l < out ) = 4 ] || { fail=1; cat out; }
|
|
grep -F 'become inacce' out || { fail=1; cat out; }
|
|
grep -F 'has appeared' out || { fail=1; cat out; }
|
|
grep '^X1$' out || { fail=1; cat out; }
|
|
grep '^X2$' out || { fail=1; cat out; }
|
|
rm -f target1 target2 out || framework_failure_
|
|
|
|
# Note other symlink edge cases are currently just diagnosed
|
|
# rather than being handled. I.E. if you specify a missing item,
|
|
# or existing file that later change to a symlink, if inotify
|
|
# is in use, you'll get a diagnostic saying that link will
|
|
# no longer be tailed.
|
|
|
|
Exit $fail
|